1. Field of the Invention
The present invention relates to a developing apparatus having a developing agent accommodating cartridge, and a cartridge for accommodating a developing agent for use in a developing apparatus.
The present invention relates to a developing apparatus having a developing agent accommodating cartridge for developing an electrostatic latent image in an electro-photography copying machine or in an electro-photography printer, and a cartridge for accommodating a developing agent for use in a developing apparatus, and, in particular, to an exchanging means for exchanging the developing agent in the developing agent accommodating cartridge.
2. Prior Art
In a conventional developing apparatus, this developing apparatus adopts a two-component developing agent in which the toners are mixed with carriers at a predetermined rate. According to the magnetic brush formed by adhering the developing agent to a developing magnet roller, an electrostatic latent image is developed by brushing and sliding a surface of the electrostatic latent image.
The toners adhered on the surfaces of the carriers are adsorbed by the electrostatic latent image and the electrostatic latent image is converted or developed to the toner image. The toners are consumed during the developing process. The toners being consumed during the developing process are supplemented using a toner accommodating cartridge.
In the above stated conventional developing apparatus, since the carriers are rubbed with the toners and further the toners are adhered repeatedly to the surfaces of the carriers, accordingly some part of the toners are fixed or spent on the surfaces of the carriers. Furthermore, then the peeling of a coating material from surfaces of the carriers occurs.
As a result, in the above stated conventional developing apparatus the surface characteristic, e.g., electrical charging characteristic, of the carriers changes, or the toners are crushed. Accordingly, the electric charging characteristic of the toners is lowered and then the life of the developing agent becomes exhausted.
The life of the developing agent is affected according to the type of the toners, the type of the carriers, an amount of the developing agent and/or the construction of the developing apparatus, etc. However, the life of the developing agent corresponds to effect the copies of several tens of thousands of pages or the printing of several tens of thousands of pages.
When the developing agent becomes exhausted, it is necessary to exchange the developing agent accommodated in the developing apparatus. However, the extracting work for extracting the developing agent from the developing apparatus is troublesome.
So as to carry out easily an exchange of developing agent, an electro-photography apparatus in which the developing apparatus itself is exchanged has been proposed. This kind of the electro-photography apparatus is disclosed in, for example, Japanese patent laid-open No. 136,767/1985.
As stated above, in the conventional developing apparatus, there is a problem in which when the developing agent becomes exhausted, the extracting work for extracting the developing agent from the developing apparatus is troublesome. Further, there is another problem that in the electro-photography apparatus when the developing apparatus itself is exchanged, the exchanging components have a high price.
In addition to the above stated problems, in the electro-photography apparatus in which it is necessary to exchange the developing apparatus itself, it is very difficult to maintain high accuracy with respect to the opposing gap between the developing magnet roller and the surface of the electrostatic latent image, and thereby it is difficult to maintain the stable developing characteristic of the developing agent in the developing apparatus.